Fig. 1
Sequence, purification, and structural analyses of endostatin (ES) variants. a Sequences of ES, zinc-binding protein-ES (ZBP-ES), mono-PEGylated ES (M 2 ES), and mono-PEGylated ZBP-ES (MZBP-ES). FL full length. b The purity of ES and its variants examined by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE). c Secondary structures of ES and its variants detected by far-ultraviolet circular dichroism (far-UV CD) spectra. d Tertiary structures of ES and its variants tested with tryptophan emission fluorescence